"réussir" with and w/o "à"

[alan gould]

I only recently encountered the latter form.  Quick research seemed to indicate they're interchangeable.  Is there a distinction?  

[George Hunt]

My quick research  seems to show that w/o "à" is  much less common than with "à".

I have no idea what the difference might be though. It would be quite minor I'd imagine.

[Neil Coffey]

It's quite subtle, but I *think* you can characterise the difference something like this:

- "réussir à" means to 'succeed' using skill/knowledge/effort/"savoir faire"

- "réussir" means to 'succeed' using something more like luck/intuition/"savoir vivre"